[lld] ELF: Add branch-to-branch optimization. (PR #138366)

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github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

<details>
<summary>
You can test this locally with the following command:
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``````````bash
git-clang-format --diff HEAD~1 HEAD --extensions cpp,h -- lld/ELF/Arch/TargetImpl.h lld/ELF/Arch/AArch64.cpp lld/ELF/Arch/X86_64.cpp lld/ELF/Config.h lld/ELF/Driver.cpp lld/ELF/Relocations.cpp lld/ELF/Target.h
``````````

</details>

<details>
<summary>
View the diff from clang-format here.
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``````````diff
diff --git a/lld/ELF/Arch/TargetImpl.h b/lld/ELF/Arch/TargetImpl.h
index bb1074951..1b2eb3108 100644
--- a/lld/ELF/Arch/TargetImpl.h
+++ b/lld/ELF/Arch/TargetImpl.h
@@ -43,8 +43,9 @@ inline void applyBranchToBranchOptImpl(
   // reading relocations of other sections.
   for (ELFFileBase *f : ctx.objectFiles) {
     auto getRelocBranchInfo =
-        [&ctx, &getBranchInfo](Relocation &r,
-               uint64_t addend) -> std::pair<Relocation *, uint64_t> {
+        [&ctx,
+         &getBranchInfo](Relocation &r,
+                         uint64_t addend) -> std::pair<Relocation *, uint64_t> {
       auto *target = dyn_cast_or_null<Defined>(r.sym);
       // We don't allow preemptible symbols (may go somewhere else),
       // absolute symbols (runtime behavior unknown), non-executable memory
@@ -54,21 +55,21 @@ inline void applyBranchToBranchOptImpl(
           target->section->kind() != SectionBase::Regular)
         return {nullptr, 0};
       return getBranchInfo(*cast<InputSection>(target->section),
-                                       target->value + addend);
+                           target->value + addend);
     };
     for (InputSectionBase *s : f->getSections()) {
       if (!s)
         continue;
       for (Relocation &r : s->relocations) {
         if (std::optional<uint64_t> addend =
-                getControlTransferAddend(*cast<InputSection>(s),
-                                                     r)) {
+                getControlTransferAddend(*cast<InputSection>(s), r)) {
           std::pair<Relocation *, uint64_t> targetAndAddend =
               getRelocBranchInfo(r, *addend);
           if (targetAndAddend.first) {
             while (1) {
               std::pair<Relocation *, uint64_t> nextTargetAndAddend =
-                  getRelocBranchInfo(*targetAndAddend.first, targetAndAddend.second);
+                  getRelocBranchInfo(*targetAndAddend.first,
+                                     targetAndAddend.second);
               if (!nextTargetAndAddend.first)
                 break;
               targetAndAddend = nextTargetAndAddend;

``````````

</details>


https://github.com/llvm/llvm-project/pull/138366